coontz0473

need some help with exhaust pro's and con's. 4" vs 5"(was told not to go with 5" unless i use programmer... if so, what programmer for 5" ex), turbo back vs cat back, (i would rather have turbo back, but concerned service engine lights will come on if i remove cat), what brand sounds best. any advice before i buy would help greatly. thanks.

Booger

You could just do a MBRP replacement muffler from Mark Craig at DPP. It is a straight through design. Then get the cat test pipe. If you remove the cat the check engine light will not come on.

hump

Welcome to the site.

5" exhaust is really not necessary utill you get up there in the higher horsepower ranges (500 + ) but several guys run a 5" system to lower the exhaust gas temps and for a better sound. Your truck should have 4" already from the turbo back, so if you wanted to go the cheaper route just replace the stock muffler with an aftermarket one for better flow and sound. Of course you can always straight pipe it Just be aware of the "drone" associated with most straight piped systems.

HUMP

coontz0473

thanks for the info. have thought about cat delete pipe and replacement muffler, but not sure how straight thru muffler will fit stock exhaust because entrance and exit are not at same height. any suggestions???

TAS05CTD610

It'll fit fine. The replacement muffler comes with a S bend to fit in place of the stock system. that is if you go with the MBRP replacement. Highly recomended in my book.

bigwheels94

Where did you hear that deleting the cat would throw a code/ That is NOT TRUE.I have had my cat off since the truck had 500 miles on it.It's really just an ash can anyway.

8mpg

I agree...I would do muffler and kitty delete, no need for 5"

sevobuck

Is there any excessive drone with the cat delete and aftermarket muffler(MBRP)? Also what about exhaust fumes... they much worse with the cat gone? I have been considering this for quite some time.

I would not go with the 5". I had that on my 02 and dang the drone was bad!!

Jmac

I thought the CAT did not restrict air flow? Does it?

Jamie

sevobuck

I am not sure but if it does not I will probably leave it in place and just get the MBRP muffler replacement.

Mark Craig

reyberg,

The exhaust smell will be the same as stock as the cats on these trucks are really soot traps and do very very little catalytic conversion like on a a gasser.

mark @ DPPI

Mark Craig

Jmac,

The cats on the 2004.5+ trucks flow well, especially as comparted to cats of just a few years ago! They are still a little restrictive though and you do drop EGT's some if you remove it, but of course you can only do that for off road and racing use, right!!

Mark @ DPPI

Mark Craig

reyberg,

If you get the MBRP muffler the sound will be close to stock except when you hammer the go pedal, then you'll get a nice deep rumble. They install easy and look stock too!

Mark @ DPPI